Musannaf Ibn Abi Shayba 13:1568

Abu Bakr narrated to us, he said: Muhammad ibn Abi ‘Adi narrated to us, from Ibn ‘Awn, from Muhammad, regarding the one who emancipates a slave while he (the slave) has wealth: He said: I prefer that it be clarified to him. If he wishes to keep it, he keeps it, and if he wishes to make it with him (the slave), he makes it.